Screw-cutting die and holder



(No Model.) S

.7 .B. H. HILMES.

'Sor ew Cutting Die and Holder. No. 240,709. Patented April 26,1881.

WITNESSES INVENTOR q TORNBYS;

MAPETERS, PNOTG-LITNOGRAPHER WASHXNGTON. D. C.

g UNITED STATES PATENT OFFICE.

BERNARD H'. HILMES, OF ALTAMONT, ILLINOIS.

SCREW-CUTTING DIE AND HOLDER.

SPECIFICATION forming part of Letters Patent No. 240,709, dated April 26, 1881.

Application filed February 18, 1881. (No model.)

To all whom it may concern:

Be it known that I, BERNARD H. HILMEs, of Altamont, in the county of Effiugham and State of Illinois, have invented a new and useful Improvement in Screw-Cutting Dies and Holders, of which the following is a speciti cation.

The object of my invention is a screw-cutting machine or implement the dies of which shall be reversible and so held and operated that after the formation of the thread the bolt may be removed from between the dies Without the necessity of unscrewing the bolt or turning the machine back.

In=the accompanying drawings, Figure 1 is a front elevation of my invention. Fig. 2 is a side view with a portion of the head and shank cut away, and Fig. 3 is a longitudinal section taken on the line :20 w of Fig. 1.

Similar letters of reference indicate correspondin g partsw A represents'the enlarged circular head, and

The ring B, which fits the periphery of the head A, is chambered out, as shown at b, and provided in a diametrical line with the squareheaded screw-bolts a a, Which pass through the ring, and the inner ends of which are rounded, as shown, to act as cams. This ring is also provided-with the screw-bolts c c, the inner ends of which are pointed and have a limited movement in the shallow grooves e e in the periphery of the circular head, which grooves have the stops 0 c for limiting the movement ofthe ring around the head.

' The front face of the head is formed with the dovetailed or undercut slot or groove 0, in which the dies D D are held, and the head is also provided with the openings E E, through which the ends of the springs F F pass. The

springs F F are secured tothe ringG, which surrounds the shank of the .holder, by the screws ff, and the ring is secured to the shank and is adjustable thereon by means of the setscrew 9. The dies D D, of the width and length to correspond. with the width and length of the groove in the face of the holder and with in connection with the bolts a a, and the rethe central opening thereof, are each formed with the thread-cutters d d for difl'ereut sizes of bolts and threads, and with the beveled ll edges to correspond with theundercut slot in the face of the head, and the corners h h of the dies are rounded, as shown, to act as cams cesses j are formed in their under sides to engage with the ends of the springs F F.

in operation the dies are brought to position and held for cutting the thread by turning the ring B upon the head of the die-holder, the screws a to having been first adjusted so that the inner rounded ends thereoflcomingin contact with the rounded corners of the dies, will 7 force the dies the proper distance toward each other. The thread having been formed by turning either the holder or the bolt by hand or mechanical power, the ring B is to be turned in a direction opposite to that first named, thus permitting the dies to be thrown back by the sprin F F, wherebyfthe bolt is released ing the same, as heretofore.

The dies may be removed from the holder and reversed by simply removing the ring 13' by unscrewing the bolts 0 c and moving back upon the shank the collar G, thus carrying the ends of the springs out of the recesses in the dies.

Having thus fully described my invention, 1 claim as new and desire to secure by Letters Patent 1. In a screw-cutting die and holder, the screw-bolts a a, provided with end cams passing through the rinf, B and acting against spring-retracted dies,as shown and described.

2. The dies D D, formed with the beveled edges 41 i and with the rounded corners h h,- and having the reeessesjj in their under side, in combination with the ring, having the setwithout the necessity and trouble of unscrewscrew g, and-with the springs F F, substan- 9c tially as and for the purposes shown and described.

BERNARD HERMANN HILMES. Witnesses:

HENRY SGHONING, P. K. J onNsoN. 

